The present invention relates to an rotatable auxiliary wheel seat of a trunk, and especially to an auxiliary wheel installed at the rear side of a trunk, as necessary, the auxiliary wheel can be ejected automatically to support the trunk obliquely and serves to assist the original corner wheels for being pulled, as unnecessary, it can be retracted for storage. In that, a special structure is designed, therefore, the original telescopic rod means serves to control the auxiliary wheel to be ejected out automatically. As a consequent, the operation becomes more conveniently.
The prior art trunk, other than a trunk body for receiving articles, includes at least two corner wheels at the bottom of the trunk body, and a telescopic rod means at the back side of the trunk body and is formed by a handle and two telescopic rods. Thereby, the user may pull the telescopic rods and then move the trunk by rolling of the two corner wheels. However, when the user holds the handle and then pulls the trunk obliquely, since the gravitation line of the trunk is shifted from the bottom of the trunk to be tilt, the user must control the tilt angle by the holding force and the feeling of the hand. During the pulling process, the gravitation center of the trunk is changed at all times, therefore, the user must adjust the holding force and direction continuously. Thus, this is not comfort in operation and use. Therefore, an auxiliary wheel seat is designed to be added to a trunk for improving the defect in the prior art.
In the prior art commercial auxiliary wheel, a pair supporting frames having a cambered sliding groove are installed at the lateral side of the back portion of the trunk, and a screwing portion is installed therein. A movable seat with sliding wheel is further pivotally installed on each supporting frame. The movable seat is driven by a driving piece at the supporting frame and a linkage on the sliding groove so as to be rotated in or out with respect to the supporting frame. A buckle with a spring and a hook are installed in the two movable seats so that as the movable seats are pushed into the supporting frame, the hook will buckle the buckling hole of the screwing portion and is hidden therein for being positioned. However, once the lower protruded portion of the hook is pushed, then it will be released so that the movable seat is rotated out. Therefore, the sliding wheel and two corner wheels are formed as a three supporting points and thus the trunk is supported steadily and the user may pull the trunk easily and comfortably.
However, in the trunk with an auxiliary wheel, since the auxiliary wheel is independently installed in a space preset in the back side of the trunk without any connection to the telescopic rod means, therefore, the operation of rotating out or in is independently and manually operated. When the user is desired to pull the trunk, the telescopic rod must be pulled out for being held and then the movable seat must be pushed, thus two steps are necessary to be performed. The operation is tedious and inconveniently. Furthermore, since the auxiliary wheel is independent from the telescopic rod means, and thus, many parts are necessary, which at least includes two supporting frames, two movable seats, a sliding wheel, a screwing portion, a cover, two driving pieces, four linkages, a cover, a buckle, a twisting spring, and a plurality of axial pins, screws and other complex structure. Not only the cost of the parts is high, but also the assembly work is complex and not economical.
Accordingly, the primary object of the present invention is to provide a rotatable auxiliary wheel seat of a trunk. Thereby, by using the telescopic rod means directly, the user is only necessary to further pull the telescopic rods after it is pulled out, then the auxiliary wheel seat will be ejected out for supporting obliquely. If a tread board is treaded, then it will retract. Not only the operation is conveniently, but also the structure is simple and can be assembled easily.
In order to achieve the aforesaid object, in the present invention, a second controller is installed, which is interacted with the first controller. When the second controller is latched, it is driven by an elastic element and is pivotally installed on the auxiliary wheel seat at the rear side of a trunk. When the telescopic rod is pulled to a first preset position, it can be held by the user to be pulled. It is only necessary to further pull the telescopic rod to a second preset position, the second controller can be acted so that the auxiliary wheel is released so as to be ejected out for supporting obliquely. Thus, the above object is achieved.
The various objects and advantages of the present invention will be more readily understood from the following detailed description when reading in conjunction with the appended drawing.